It all depends on you
I have heard and read just about every possible theory on what does or does not make a survival weapon.
It all depends on your situation, I own many guns of various calibers and styles and being that I live in a southern state my needs will be far different than those that live in the Mid West or Northern areas.
To protect my self and to get me to where I need to go in the classic TEOTWAWKI situation it would be My Arsenal SLR 107-f AK-47 Why ?
It always goes BOOM it does not need to be wined and dined The Damn things are indestructible The 7.62x.39 is a more devastating round than a .223
An AR 15 will keep you pinned down behind a car An AK will go thru the car.
That is why since 1947 no one has been able to make a weapon system as reliable as an AK. If you dont Clean it for 6 months and shoot any and every type of ammo thru it it still works.
Try that with an AR You wont.
Now with that being said I carry a Ruger 10/22 with me every where I go when I travel more than 10 miles from my home in a tactical bag with 600 rounds of ammo.
If you need to live off the land you dont want an AK or an AR The .22 cartridge will keep you well fed until help arrives or until you rescue your self.
So depending on your situation you dont bring a knife to a gum fight and you dont try to kill squirrels nutria rats or rabbits with an assault rifle .
But more than anything Carry your brain because if you dont you will be a well armed well equipped dead moron WAKE UP PEOPLE